Rotary cutter head



Dec. 25 1923. E@

o. R. GUsTAFsoN ROTARY CUTTER HEAD' Filed July 18. 1921 Patented Der; 25, 1923.,

t@ FF i. ratte FTENF @FF OSCAR R. GUSTAFSON, OF CHICAGO, ILLINSIS, ASSIGNQR GF ONE-HALF TO vGEORGE S. SCOTT, OF CHICAGO, ILLINOIS. v

ROTARY CUTTER HEAD.

Application led July 1S,

To all whom 'it may concer/ni:

Be it known that I, OSCAR R. GUsTAFsoN, a citizen of the United States, residing at Chicago, Cook County, Illinois, yhave invented certain new and useful Improvements Relating to Rotary Cutter Heads, of which the following is a specification.

One of the objects of the present improvements is to provide simple and easily operable means for securely holding the cutter blade in operative position, while providing for a ready and substantially inexpensive substitution of holding parts worn out in service. Another object is to provide improved means for adjusting the blade.

In the accompanying drawings, which form a part of this specification, Figure 1 is an end view of a four-blade rotary cutter head showing the blades and blade keepers in operative position; Fig. 2 is a cross section on the line 2-2 of Fig. 4; Fig. 3 is a similar section on the line 3-3 of Fig. 4; Fig. 4 is a side view of the-cutter head; Fig. 5 is a view of a tool for operating the clamping means; Fig. 6 is a face view'of the keeper; and Fig. 7 is a perspective, on an enlarged scale, of the readily removable clamping members.`

Since the four blade units shown are alike a single description only is required. The number of such units may be greater or less.l and the cutter head may have any desired practical length and diameter.

The blade 10 and the blade keeper 11 are shown as of usual form and are accommodated in the usual longitudinally extending recess 12 having a seat at 13 against which the blade is held.

Turning to Figs. 2 and 7 my improved locking device includes a nut member having a cylindrical sleeve-like part 14 interiorly threaded and having a head or flange 15 which is shown as rectangular and slanted off' along one edge to provide clearance for the follower 11. This cylindricalbody 14 lits loosely in a cylindrical hole 16 which is bored from the peripheral surface vofthe cutter head toward and into the recess 12 adjacent to the keeper 11. The recess 12l is enlargedby a longitudinal recess 17 toprovide space for the flange 15 and a seat adjacent to the flange as at 19 whereby the flange seated against the metal about the hole 16 at the recess 17 holds the nut member 14 against retraction or movement in 192i. semi No. 485,692.

the hole 16 in a direction away from the keeper.

Threaded into the nut member is the cylindrical bolt-like threaded member 20,' having theI forward central stud 21 adapted to impinge against the keeper 11, the keeper being provided with a recessed scat 22 for the stud 21 and thekeeper being thus positively held against outward movement when the device is in use. The threaded member` 20 has a polygonall hole 23, shown vas hex.L agonal, to accommodate the correspondingly-shaped stem 24 of the wrench 25.

It is thus clear that by means of the wrench 25 the threaded member 20 may be advanced in the nut member V14 until the stud 21 strongly impinges upon the keeper and the knife or blade 10 is tightly clamped in operative position.`

The length of the nut member 14 is such that by retracting and removing'the threaded member 2O and also removing the keeper and blade from the recess 12 the nut member may be taken bodily out of its retaining hole 16 and removed through the recess as 17 and 12. i

In holding such a cutter blade operatively in position it must be bound quite tightly, with correspondingly great strain and consequent wear and tear upon the threaded part-s. The cutter head' as a whole is a relatively quite expensive piece of'mechanism and is so strong and durable as to last indefinitely. According to these improvements an exceedingly simple and cheap ,clamping device may be replaced from time to time as required and in a very brief space of time, andwithout removing the cutter head from the machine. y

A second feature of improvement is illustrated in Fig. 3 and consists in provisions for the use of aprying toolas 25 for forcing the blade as 10 in an outward direction for purposes of adjustment when the blade is repositioned after sharpening. Various suggestions have heretofore been made for adi-py justably moving the blade.

A To provide access for the prying tool V,or lever 25 I form a Slot-like opening 26 which l extends from the periphery of the cutter head to the recess. 12 on the bladeA side. the' slot-like opening 26 being relatively long in the circumferential direct-ion of the head,r and the end wall thereof which is adjacent to the lower edge of the blade 10 being so directed as to form with the blade an acute angle, the outer portion of this end wall thereby forming a fulcrum which is so positioned as to be effective when the blade 10 is moved in the outwardr direction a relatively great dista-nce, as shown by the dotted lines of Fig. 3. The recess 26 extends so far into the metal adjacent to the lower edge of the cutter that the prying tool can be applied to this lower edge of the blade when the blade is otherwise vseated in the bottom of 'the recess 12.

In using the prying tool for moving the blade the'clamping screw 20 is brought to bear against thel keeper with only sufiicient force to hold the blade against movement by its own weight. The prying tool is applied first at one end of the blade and then atV the other, and `also in the middle if desired,

and by means of suitable leverage pressureupon' the tool the blade is gradually moved into its desired position, after which Vthe locking devices are operated to clamp the keeper and blade firmly.

Such prying action for adjusting the blade is unusually advantageous since the operator is enabled to exert the necessary force and move the blade in small degrees in a very easy and expeditious way and theadjustments y'may be vmade throughout an unusually large range of movement, thus enabling the blade to be continued in use until it has been made quite narrow from successive grindings. The adjustment of the blade may always be made without removing the cutter from the machine.

While I have thus illustrated and described 'preferred embodiments respectively of these two principal features of improvement, I contemplate as being within the scope of the invention var-ious modifications in details of construction as indicated by the appended claims.

I claim:

l. The combination of a cutter head having a longitudinalrecess for accommodating a cutter blade and a keeper therefor, a cutter blade and a keeper side by side in said recess, the head having a holeextending from 'its peripheral surface toward rand into said recess adjacent to the keeper, a readily removable nut member having a sleeve part loosely fitting in said hole and having a flanged .part adjacentv to the keeper for holding the nut member against rotation and against movement in said hole in a direction away fromvthe-keeper, a threaded.V member vpassin-g through the nut memberv andiimpingingthe keeper to hold thel blade g in the recess, saidV threaded member having means at its outer. end portion for rotating it in the threading and unthreading directions, said nut member having such length i that when the blade and keeper are removed from said recess the nut member mayl be removed from its containing hole through the recess after removing the threaded member from the nut member.

2. The combination of a cutter head hav-V ing a longitudinal recess for accommodating a cutter blade and a keeper therefor,y a

cutter blade and a keeper side by side in A said recess, means for clamping the keeper tightly upon the cutter blade to. hold the blade firmly in said recess, the head-having a slot-like opening extending from the peripheral surface of the head inwardly'tor said recess adjacent to the blade and beyond Y great distance by such prying lever action.'V 1

3. The combination of a cutter head having a longitudinal recess for accommodating a cutter blade and ka keeper therefor, a cutter blade and a keeper side by side in said recess, the head having a hole extending from its peripheral Vsurface toward and into said recess adjacent to the keeper, a readily removable nut member extending into said hole,` a threaded member passing through the. nut member and impinging the keeper to hold the blade in the recess, said threaded member having means at its outer end portion for rotating it in the threading and unthreading directions, said nut member having such length that rwhen the-blade and keeper are removed from said recess the nut member may be removed from saidk hole and from the head by passing the nut member into said recess and then out of said recess, after Vremoving the threaded member from the nutmember, Athe nut member having laterally extending portions adjacent to its inner end to constitutea stop for limiting the movement of the nut member in a direction away from saidiecess and for holding the nut member against rotation when the threaded memberis rotated, said hole beingPv formed to accom'- modate said laterally extending portions of the nut member.

OSCAR, R. GUSTAFSON. 

